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Deng P, Peng Y, Sheng Z, Li W, Liu Y. RNAi silencing CHS1 gene shortens the mortality time of Plutella xylostella feeding Bt-transgenic Brassica napus. PEST MANAGEMENT SCIENCE 2024; 80:2610-2618. [PMID: 38252693 DOI: 10.1002/ps.7968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 01/03/2024] [Accepted: 01/07/2024] [Indexed: 01/24/2024]
Abstract
BACKGROUND Insect-resistance genetically modified (GM) plants derived from Bacillus thuringiensis (Bt) have been cultivated to control pests, but continuous cultivation of Bt-transgenic plants at large-scale regions leads to the resistance evolution of target insects to transgenic plants. RNA interference (RNAi) technology is considered an effective strategy in delaying the resistance evolution of target insects. RESULTS We here developed a single transgenic oilseed rape (Brassica napus) line with hairpin RNA of the chitin-synthase 1 gene (CHS1) of Plutella xylostella (hpPxCHS1) and a pyramid transgenic B. napus line harboring hpPxCHS1 and Bt gene (Cry1Ac). Escherichia coli HT115 delivered hpPxCHS1 showed negative effects on the growth of P. xylostella. The single transgenic and pyramid transgenic B. napus significantly reduced the larval weight and length of P. xylostella and increased its lethality rate, with down-regulation expression of the PxCHS1 gene in insects. CONCLUSION Compared to Bt-transgenic B. napus, pyramid-transgenic B. napus shorted the mortality time of P. xylostella, indicating that RNAi technology synergistic with Bt protein improves the effectiveness of controlling target insects. Our results proved that RNAi can delay the resistance evolution of target insects to Bt-transgenic plants. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Purong Deng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
- State Environmental Protection Key Laboratory of Regional Eco-process and Function Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
| | - Yujia Peng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
- State Environmental Protection Key Laboratory of Regional Eco-process and Function Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
| | - Zhilu Sheng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
- State Environmental Protection Key Laboratory of Regional Eco-process and Function Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
| | - Wencui Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
- State Environmental Protection Key Laboratory of Regional Eco-process and Function Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
| | - Yongbo Liu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
- State Environmental Protection Key Laboratory of Regional Eco-process and Function Assessment, Chinese Research Academy of Environmental Sciences, Beijing, China
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Yu A, Beck M, Merzendorfer H, Yang Q. Advances in understanding insect chitin biosynthesis. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2024; 164:104058. [PMID: 38072083 DOI: 10.1016/j.ibmb.2023.104058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 12/04/2023] [Accepted: 12/05/2023] [Indexed: 12/17/2023]
Abstract
Chitin, a natural polymer of N-acetylglucosamine chains, is a principal component of the apical extracellular matrix in arthropods. Chitin microfibrils serve as structural components of natural biocomposites present in the extracellular matrix of a variety of invertebrates including sponges, molluscs, nematodes, fungi and arthropods. In this review, we summarize the frontier advances of insect chitin synthesis. More specifically, we focus on the chitin synthase (CHS), which catalyzes the key biosynthesis step. CHS is also known as an attractive insecticidal target in that this enzyme is absent in mammals, birds or plants. As no insect chitin synthase structure have been reported so far, we review recent studies on glycosyltransferase domain structures derived from fungi and oomycetes, which are conserved in CHS from all species containing chitin. Auxiliary proteins, which coordinate with CHS in chitin biosynthesis and assembly, are also discussed.
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Affiliation(s)
- Ailing Yu
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China; State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Marius Beck
- Department of Chemistry-Biology, University of Siegen, Siegen, Germany
| | - Hans Merzendorfer
- Department of Chemistry-Biology, University of Siegen, Siegen, Germany.
| | - Qing Yang
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China; State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
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3
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Zhang C, Ding Y, Zhou M, Tang Y, Chen R, Chen Y, Wen Y, Wang S. RNAi-mediated CHS-2 silencing affects the synthesis of chitin and the formation of the peritrophic membrane in the midgut of Aedes albopictus larvae. Parasit Vectors 2023; 16:259. [PMID: 37533099 PMCID: PMC10394979 DOI: 10.1186/s13071-023-05865-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 07/04/2023] [Indexed: 08/04/2023] Open
Abstract
BACKGROUND Mosquitoes are an important vector of viral transmission, and due to the complexity of the pathogens they transmit, vector control may be the most effective strategy to control mosquito-borne diseases. Chitin is required for insect growth and development and is absent in higher animals and plants, so regulating the chitin synthesis pathway can serve as a potentially effective means to control vector insects. Most of the current research on the chitin synthase (CHS) gene is focused on chitin synthase-1 (CHS-1), while relatively little is known about chitin synthase-2 (CHS-2). RESULTS The CHS-2 gene of Ae. albopictus is highly conserved and closely related to that of Aedes aegypti. The expression of CHS-2 in the third-instar larvae and pupal stage of Ae. albopictus was relatively high, and CHS-2 expression in adult mosquitoes reached the highest value 24 h after blood-feeding. In the fourth-instar larvae of Ae. albopictus, CHS-2 expression was significantly higher in the midgut than in the epidermis. Silencing CHS-2 in Ae. albopictus larvae had no effect on larval survival and emergence. The expression of four genes related to chitin synthesis enzymes was significantly upregulated, the expression level of three genes was unchanged, and only the expression level of GFAT was significantly downregulated. The expression of chitin metabolism-related genes was also upregulated after silencing. The level of chitin in the midgut of Ae. albopictus larvae was significantly decreased, while the chitinase activity was unchanged. The epithelium of the midgut showed vacuolization, cell invagination and partial cell rupture, and the structure of the peritrophic membrane was destroyed or even absent. METHODS The expression of CHS-2 in different developmental stages and tissues of Aedes albopictus was detected by real-time fluorescence quantitative PCR (qPCR). After silencing CHS-2 of the fourth-instar larvae of Ae. albopictus by RNA interference (RNAi), the expression levels of genes related to chitin metabolism, chitin content and chitinase activity in the larvae were detected. The structure of peritrophic membrane in the midgut of the fourth-instar larvae after silencing was observed by paraffin section and hematoxylin-eosin (HE) staining. CONCLUSION CHS-2 can affect midgut chitin synthesis and breakdown by regulating chitin metabolic pathway-related genes and is involved in the formation of the midgut peritrophic membrane in Ae. albopictus, playing an important role in growth and development. It may be a potential target for enhancing other control methods.
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Affiliation(s)
- Chen Zhang
- Hangzhou Normal University, Hangzhou, China
| | | | - Min Zhou
- Hangzhou Normal University, Hangzhou, China
| | - Ya Tang
- Hangzhou Normal University, Hangzhou, China
| | - Rufei Chen
- Hangzhou Normal University, Hangzhou, China
| | | | - Yating Wen
- Hangzhou Normal University, Hangzhou, China
| | - Shigui Wang
- Hangzhou Normal University, Hangzhou, China.
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Zeng B, Chen FR, Sun H, Liu Y, Wu SF, Bass C, Gao CF. Molecular and functional analysis of chitin synthase genes in Chilo suppressalis (Lepidoptera: Crambidae). INSECT SCIENCE 2023; 30:661-676. [PMID: 36269029 DOI: 10.1111/1744-7917.13134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 09/19/2022] [Accepted: 10/07/2022] [Indexed: 06/15/2023]
Abstract
The rice stem borer, Chilo suppressalis, has developed a high level of resistance to many of the compounds currently used for control. There is therefore an urgent need to develop novel control methods for C. suppressalis. Insect chitin synthases (CHS) have attracted interest as a potential target for insect pest management. However, to date, CHS have not been characterized in C. suppressalis. Two CHS genes (CsCHS1 and CsCHS2) were identified and cloned from C. suppressalis. Two transcript variants were identified for CsCHS1, CsCHS1a and CsCHS1b. Spatiotemporal expression profiling showed that both transcripts of CsCHS1 are most highly expressed on the last day of each larval instar stage and show the highest expression levels in the integument. In contrast, CsCHS2 is predominantly expressed during the larval feeding stages and shows the highest expression levels in the midgut. Knockdown of CsCHS1 by RNA interference significantly inhibited the molting and pupation of C. suppressalis, and knockdown of CsCHS2 significantly affected growth during the larval stage, but had no significant effect on the pupation. Moreover, knockout of CsCHS1 by CRISPR/Cas9 genome editing severely lowered the hatching rate, larval survivorship, pupation rate, and eclosion rate, but only larval survivorship at the G0 generation was lowered after the knockout of CsCHS2. These results demonstrate that CsCHS1 and CsCHS2 play vital roles in the growth and development of C. suppressalis, and so have potential as insecticidal targets for the control of this highly damaging pest.
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Affiliation(s)
- Bin Zeng
- State & Local Joint Engineering Research Center of Green Pesticide Invention and Application/College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- College of Life and Environmental Sciences, Biosciences, University of Exeter, Penryn, UK
| | - Fu-Rong Chen
- State & Local Joint Engineering Research Center of Green Pesticide Invention and Application/College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Hao Sun
- State & Local Joint Engineering Research Center of Green Pesticide Invention and Application/College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Yan Liu
- State & Local Joint Engineering Research Center of Green Pesticide Invention and Application/College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Shun-Fan Wu
- State & Local Joint Engineering Research Center of Green Pesticide Invention and Application/College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Chris Bass
- College of Life and Environmental Sciences, Biosciences, University of Exeter, Penryn, UK
| | - Cong-Fen Gao
- State & Local Joint Engineering Research Center of Green Pesticide Invention and Application/College of Plant Protection, Nanjing Agricultural University, Nanjing, China
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Müller R, Bálint M, Hardes K, Hollert H, Klimpel S, Knorr E, Kochmann J, Lee KZ, Mehring M, Pauls SU, Smets G, Steinbrink A, Vilcinskas A. RNA interference to combat the Asian tiger mosquito in Europe: A pathway from design of an innovative vector control tool to its application. Biotechnol Adv 2023; 66:108167. [PMID: 37164239 DOI: 10.1016/j.biotechadv.2023.108167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 04/06/2023] [Accepted: 04/30/2023] [Indexed: 05/12/2023]
Abstract
The Asian tiger mosquito Aedes albopictus is currently spreading across Europe, facilitated by climate change and global transportation. It is a vector of arboviruses causing human diseases such as chikungunya, dengue hemorrhagic fever and Zika fever. For the majority of these diseases, no vaccines or therapeutics are available. Options for the control of Ae. albopictus are limited by European regulations introduced to protect biodiversity by restricting or phasing out the use of pesticides, genetically modified organisms (GMOs) or products of genome editing. Alternative solutions are thus urgently needed to avoid a future scenario in which Europe faces a choice between prioritizing human health or biodiversity when it comes to Aedes-vectored pathogens. To ensure regulatory compliance and public acceptance, these solutions should preferably not be based on chemicals or GMOs and must be cost-efficient and specific. The present review aims to synthesize available evidence on RNAi-based mosquito vector control and its potential for application in the European Union. The recent literature has identified some potential target sites in Ae. albopictus and formulations for delivery. However, we found little information concerning non-target effects on the environment or human health, on social aspects, regulatory frameworks, or on management perspectives. We propose optimal designs for RNAi-based vector control tools against Ae. albopictus (target product profiles), discuss their efficacy and reflect on potential risks to environmental health and the importance of societal aspects. The roadmap from design to application will provide readers with a comprehensive perspective on the application of emerging RNAi-based vector control tools for the suppression of Ae. albopictus populations with special focus on Europe.
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Affiliation(s)
- Ruth Müller
- Unit Entomology, Institute of Tropical Medicine, Nationalestraat 155, 2000 Antwerp, Belgium; Institute of Occupational, Social and Environmental Medicine, Goethe University, Theodor-Stern-Kai 9, 60590 Frankfurt am Main, Germany
| | - Miklós Bálint
- Senckenberg Biodiversity and Climate Research Centre (SBiK-F), Georg-Voigt-Str. 14-16, 60325 Frankfurt am Main, Germany; LOEWE Centre for Translational Biodiversity Genomics (LOEWE TBG), Senckenberganlage 25, 60325 Frankfurt am Main, Germany; Institute for Insect Biotechnology, Justus-Liebig University, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany
| | - Kornelia Hardes
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE TBG), Senckenberganlage 25, 60325 Frankfurt am Main, Germany; Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Branch of Bioresources, Ohlebergsweg 12, 35392 Giessen, Germany; BMBF Junior Research Group in Infection Research "ASCRIBE", Germany
| | - Henner Hollert
- Senckenberg Biodiversity and Climate Research Centre (SBiK-F), Georg-Voigt-Str. 14-16, 60325 Frankfurt am Main, Germany; Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Department Media-related Toxicity, Max-von-Laue-Str. 13, 60438 Frankfurt am Main, Germany; Evolutionary Ecology and Environmental Toxicology, Institute for Ecology, Evolution and Diversity, Goethe University Frankfurt, Max-von-Laue-Str. 13, 60438 Frankfurt am Main, Germany
| | - Sven Klimpel
- Senckenberg Biodiversity and Climate Research Centre (SBiK-F), Georg-Voigt-Str. 14-16, 60325 Frankfurt am Main, Germany; LOEWE Centre for Translational Biodiversity Genomics (LOEWE TBG), Senckenberganlage 25, 60325 Frankfurt am Main, Germany; Integrative Parasitology and Zoophysiology, Institute for Ecology, Evolution and Diversity, Goethe University Frankfurt, Max-von-Laue-Str. 13, 60438 Frankfurt am Main, Germany
| | - Eileen Knorr
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Branch of Bioresources, Ohlebergsweg 12, 35392 Giessen, Germany
| | - Judith Kochmann
- Senckenberg Biodiversity and Climate Research Centre (SBiK-F), Georg-Voigt-Str. 14-16, 60325 Frankfurt am Main, Germany
| | - Kwang-Zin Lee
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Branch of Bioresources, Ohlebergsweg 12, 35392 Giessen, Germany
| | - Marion Mehring
- Senckenberg Biodiversity and Climate Research Centre (SBiK-F), Georg-Voigt-Str. 14-16, 60325 Frankfurt am Main, Germany; ISOE - Institute for Social-Ecological Research, Hamburger Allee 45, 60486 Frankfurt am Main, Germany
| | - Steffen U Pauls
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE TBG), Senckenberganlage 25, 60325 Frankfurt am Main, Germany; Institute for Insect Biotechnology, Justus-Liebig University, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany; Senckenberg Research Institute and Natural History Museum Frankfurt, Senckenberganlage 25, 60325 Frankfurt am Main, Germany
| | - Greet Smets
- Perseus BV, Kortrijksesteenweg 127 B1, B-9830 Sint-Martens-Latem, Belgium
| | - Antje Steinbrink
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE TBG), Senckenberganlage 25, 60325 Frankfurt am Main, Germany; Institute for Insect Biotechnology, Justus-Liebig University, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany
| | - Andreas Vilcinskas
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE TBG), Senckenberganlage 25, 60325 Frankfurt am Main, Germany; Institute for Insect Biotechnology, Justus-Liebig University, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany; Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Branch of Bioresources, Ohlebergsweg 12, 35392 Giessen, Germany.
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Das J, Kumar R, Shah V, Raghavendra KP, Sharma AK. Identification and functional characterisation of N-acetylglucosamine kinase from Helicoverpa armigera divulge its potential role in growth and development via UDP-GlcNAc salvage pathway. Int J Biol Macromol 2023; 242:124674. [PMID: 37137348 DOI: 10.1016/j.ijbiomac.2023.124674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 04/17/2023] [Accepted: 04/27/2023] [Indexed: 05/05/2023]
Abstract
N-acetylglucosamine kinase (NAGK), a major enzyme of sugar-kinase/Hsp70/actin superfamily, catalyses the conversion of N-acetylglucosamine to GlcNAc-6-phosphate, the first step leading to the salvage synthesis of uridine diphosphate N-acetylglucosamine. Here, we present the first report on identification, cloning, recombinant expression and functional characterisation of NAGK from Helicoverpa armigera (HaNAGK). The purified soluble HaNAGK exhibited a molecular mass of ~39 kDa with monomeric conformation. It catalysed the sequential transformation of GlcNAc into UDP-GlcNAc, indicating its role as the initiator of UDP-GlcNAc salvage pathway. HaNAGK exhibited ubiquitous expressions across all the developmental stages and major tissues of H. armigera. The gene was significantly upregulated (80 %; p < 0.01) by the moulting hormone 20-hydroxyecdysone and significantly downregulated (89 %; p < 0.001) by the chitin synthesis inhibitor novaluron, indicating its involvement in ecdysis and chitin metabolism. Furthermore, RNAi of HaNAGK caused poor weight gain, deformed insect bodies, aberrant metamorphosis and pronounced wing abnormalities in >55 % of surviving adults, while recording 7.79 ± 1.52 % and 24.25 ± 7.21 % mortality during larval and pupal stages, respectively. Altogether, the present findings suggest that HaNAGK plays a crucial role in the growth and development of H. armigera and thus, could be considered as a compelling gene of interest while formulating novel pest management strategies.
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Affiliation(s)
- Joy Das
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Uttarakhand, India; ICAR-Central Institute for Cotton Research, Nagpur, Maharashtra, India
| | - Rakesh Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Uttarakhand, India; ICAR-Central Institute for Cotton Research, Nagpur, Maharashtra, India
| | - Vivek Shah
- ICAR-Central Institute for Cotton Research, Nagpur, Maharashtra, India
| | - K P Raghavendra
- ICAR-Central Institute for Cotton Research, Nagpur, Maharashtra, India
| | - Ashwani Kumar Sharma
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Uttarakhand, India.
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Ren M, Lu J, Li D, Yang J, Zhang Y, Dong J, Niu Y, Zhou X, Zhang X. Identification and Functional Characterization of Two Chitin Synthases in the Black Cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae). JOURNAL OF ECONOMIC ENTOMOLOGY 2023; 116:574-583. [PMID: 36757382 DOI: 10.1093/jee/toac193] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Indexed: 05/30/2023]
Abstract
The black cutworm, Agrotis ipsilon (Hufnagel), a seasonal migrant and a prolific generalist, can feed on nearly all vegetables and grain crops, causing considerable economic impacts on a global scale. Given its cryptic nature, A. ipsilon management has been extremely challenging. Chitin synthase (CHS), a key enzyme involved in chitin biosynthetic pathway and crucially important for the growth and development of insects, is the molecular target of chitin synthesis inhibitors, a group of broad-spectrum insecticides that is compatible with Integrated Pest Management practices. In this study, we investigated the potential of targeting chitin synthases to control A. ipsilon. As a result, two chitin synthases, AiCHS1 and AiCHS2, were identified and cloned from A. ipsilon. The temporal-spatial distribution study showed that AiCHS1 was predominantly expressed at the pupal stage and most abundant among tissues of head capsule and integument, while AiCHS2 was mainly expressed at the sixth instar larval stage and tissues of foregut and midgut. RNAi-based functional study confirmed gene silencing caused significant reduction in the expression levels of the corresponding mRNA, as well as resulted in abnormal pupation and mortality, respectively. Furthermore, under the treatment of lufenuron, a chitin synthesis inhibitor, A. ipsilon responded with an elevated expression in AiCHS1 and AiCHS2, while larvae showed difficulty in shedding old cuticle, and a cumulative mortality of 69.24% at 48 h. In summary, chitin synthases are crucial for chitin biosynthesis in A. ipsilon and can be targeted for the control (e.g., RNAi-based biopesticides) of this devastating insect pest.
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Affiliation(s)
- Meifeng Ren
- College of Plant Protection, Shanxi Agricultural University, Taiyuan, China
| | - Junjiao Lu
- College of Plant Protection, Shanxi Agricultural University, Taiyuan, China
| | - Daqi Li
- College of Plant Protection, Shanxi Agricultural University, Taiyuan, China
| | - Jing Yang
- College of Plant Protection, Shanxi Agricultural University, Taiyuan, China
| | - Yuying Zhang
- College of Plant Protection, Hunan Agricultural University, Changsha, China
| | - Jinming Dong
- College of Plant Protection, Shanxi Agricultural University, Taiyuan, China
| | - Yanbing Niu
- College of Life Sciences, Shanxi Agricultural University, Taigu, China
| | - Xuguo Zhou
- Department of Entomology, University of Kentucky, Lexington, KY, USA
| | - Xianhong Zhang
- College of Plant Protection, Shanxi Agricultural University, Taiyuan, China
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Adeyinka OS, Nasir IA, Tabassum B. Host-induced silencing of the CpCHI gene resulted in developmental abnormalities and mortality in maize stem borer (Chilo partellus). PLoS One 2023; 18:e0280963. [PMID: 36745624 PMCID: PMC9901779 DOI: 10.1371/journal.pone.0280963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 01/11/2023] [Indexed: 02/07/2023] Open
Abstract
RNAi-based insecticides for crop protection have witnessed rapid improvement over the years. However, their potential to efficiently control maize stem borer (Chilo partellus) pests has remained underexplored. In this study, double-stranded C. partellus chitinase (dsCHI) toxicity was investigated in C. partellus larvae. Furthermore, we developed transgenic maize lines expressing dsRNA targeted against C. partellus chitinase transcripts and performed detached leaf insect feeding bioassays. Our results revealed that C. partellus chitinase transcript expression was significantly downregulated by 57% and 82% in the larvae. Larvae exhibited various phenotypic distortion levels across developmental stages, and 53% mortality occurred in transgenic fed larvae compared to those fed on nontransgenic leaves. In conclusion, we have identified the C. partellus chitinase gene as a potential target for RNAi-mediated control and demonstrated that oral delivery via bacteria and plant-mediated delivery are viable means of achieving C. partellus RNAi-mediated control.
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Affiliation(s)
- Olawale Samuel Adeyinka
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
- Department of Chemistry, Physics and Atmospheric Sciences Jackson state University, Jackson, MS, United States of America
- * E-mail:
| | - Idrees Ahmad Nasir
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Bushra Tabassum
- Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
- School of Biological Sciences, University of the Punjab, Lahore, Pakistan
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9
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Das J, Kumar R, Shah V, Sharma AK. Functional characterization of chitin synthesis pathway genes, HaAGM and HaUAP, reveal their crucial roles in ecdysis and survival of Helicoverpa armigera (Hübner). PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2022; 188:105273. [PMID: 36464378 DOI: 10.1016/j.pestbp.2022.105273] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/26/2022] [Accepted: 10/23/2022] [Indexed: 06/17/2023]
Abstract
The chitin metabolic pathway is one of the most lucrative targets for designing pest management regimes. Inhibition of the chitin synthesis pathway causes detrimental effects on the normal growth and development of insects. Phospho-N-acetylglucosamine mutase (AGM) and UDP-N-acetylglucosamine pyrophosphorylase (UAP) are two key chitin biosynthesis enzymes in insects including Helicoverpa armigera, a pest of global significance. In the present study, we have identified, cloned and recombinantly expressed AGM and UAP from H. armigera (HaAGM and HaUAP). Biochemical characterization of recombinant HaAGM and HaUAP exhibited high affinities for their natural substrates N-acetyl glucosamine-6-phosphate (Km 38.72 ± 2.41) and N-acetyl glucosamine-1-phosphate (Km 3.66 ± 0.13), respectively. In the coupled enzyme-catalytic assay, HaAGM and HaUAP yielded the end-products, inorganic pyrophosphate and UDP-GlcNAc, confirming their active participation in the chitin synthesis pathway of H. armigera. Gene expression profiling revealed that HaAGM and HaUAP genes were expressed in all developmental stages and key tissues. These genes also showed substantial responses towards the moulting hormone 20-hydroxyecdysone and chitin biosynthesis inhibitor, novaluron. Remarkably, the RNAi-mediated knockdown of either HaAGM or HaUAP led to severe developmental deformities and significant mortality ranging from 65.61 to 72.54%. Overall findings suggest that HaAGM and HaUAP play crucial roles in the ecdysis and survival of H. armigera. Further, these genes could serve as potential targets for designing pest management strategies for H. armigera.
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Affiliation(s)
- Joy Das
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Uttarakhand, India; ICAR-Central Institute for Cotton Research, Nagpur, Maharashtra, India
| | - Rakesh Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Uttarakhand, India; ICAR-Central Institute for Cotton Research, Nagpur, Maharashtra, India
| | - Vivek Shah
- ICAR-Central Institute for Cotton Research, Nagpur, Maharashtra, India
| | - Ashwani Kumar Sharma
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Uttarakhand, India.
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Li X, Liu X, Lu W, Yin X, An S. Application progress of plant-mediated RNAi in pest control. Front Bioeng Biotechnol 2022; 10:963026. [PMID: 36003536 PMCID: PMC9393288 DOI: 10.3389/fbioe.2022.963026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 07/11/2022] [Indexed: 01/09/2023] Open
Abstract
RNA interference (RNAi)-based biopesticides are novel biologic products, developed using RNAi principles. They are engineered to target genes of agricultural diseases, insects, and weeds, interfering with their target gene expression so as to hinder their growth and alleviate their damaging effects on crops. RNAi-based biopesticides are broadly classified into resistant plant-based plant-incorporated protectants (PIPs) and non-plant-incorporated protectants. PIP RNAi-based biopesticides are novel biopesticides that combine the advantages of RNAi and resistant transgenic crops. Such RNAi-based biopesticides are developed through nuclear or plastid transformation to breed resistant plants, i.e., dsRNA-expressing transgenic plants. The dsRNA of target genes is expressed in the plant cell, with pest and disease control being achieved through plant-target organism interactions. Here, we review the action mechanism and strategies of RNAi for pest management, the development of RNAi-based transgenic plant, and the current status and advantages of deploying these products for pest control, as well as the future research directions and problems in production and commercialization. Overall, this study aims to elucidate the current development status of RNAi-based biopesticides and provide guidelines for future research.
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Mao C, Zhu X, Wang P, Sun Y, Huang R, Zhao M, Hull JJ, Lin Y, Zhou F, Chen H, Ma W. Transgenic double-stranded RNA rice, a potential strategy for controlling striped stem borer (Chilo suppressalis). PEST MANAGEMENT SCIENCE 2022; 78:785-792. [PMID: 34713554 DOI: 10.1002/ps.6692] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 10/20/2021] [Accepted: 10/28/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Although the striped stem borer (SSB, Chilo suppressalis Walker) is a devastating pest of rice that causes significant economic losses, management options are currently limited. Plant-mediated RNA interference (RNAi) is an emerging crop protection technique in which transgenic plants are modified to express insect-specific double-stranded RNAs (dsRNAs) that trigger RNAi silencing in target pests. RESULT In this study, an RNAi-based screen of 35 candidate SSB genes identified a small heat shock protein gene (CssHsp) as a potential plant-based RNAi target. To assess its utility in planta, a total of 39 transgenic rice plants were generated, with 11 independent transformants found to contain a single copy of the dsCssHsp expression cassette. In life-time feeding bioassays, three transgenic lines (DS10, DS35, DS36) were found to have significant negative impacts on SSB populations. After feeding for 8 days, mortality in the three transgenic lines exceeded 60%. By pupation, mortality further increased to 90% and few SSB survived to eclosion. Gene expression analyses confirmed that CssHsp transcript levels were significantly reduced after feeding on the transgenic dsCssHsp rice. CONCLUSION These results demonstrate the potential for developing a plant-mediated RNAi strategy targeting CssHsp as a more biorational field-based approach for SSB control. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Cui Mao
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Xiaoping Zhu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Peipei Wang
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Yajie Sun
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Renliang Huang
- Nanchang Subcenter of Rice National Engineering Laboratory, Key Laboratory of Rice Physiology and Genetics of Jiangxi Province, Rice Research Institute, Jiangxi Academy of Agricultural Sciences, Nanchang, China
| | - Mingchao Zhao
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - J Joe Hull
- Pest Management and Biocontrol Research Unit, US Arid Land Agricultural Research Center, USDA Agricultural Research Services, Maricopa, AZ, USA
| | - Yongjun Lin
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Fei Zhou
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Hao Chen
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Weihua Ma
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
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Khalil SMS, Munawar K, Alahmed AM, Mohammed AMA. RNAi-Mediated Screening of Selected Target Genes Against Culex quinquefasciatus (Diptera: Culicidae). JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:2177-2185. [PMID: 34197598 DOI: 10.1093/jme/tjab114] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Indexed: 06/13/2023]
Abstract
Culex quinquefasciatus, a member of the Culex pipiens complex, is widespread in Saudi Arabia and other parts of the world. It is a vector for lymphatic filariasis, Rift Valley fever, and West Nile virus. Studies have shown the deleterious effect of RNA interference (RNAi)-mediated knockdown of various lethal genes in model and agricultural pest insects. RNAi was proposed as a tool for mosquito control with a focus on Aedes aegypti and Anopheles gambiae. In this study, we examined the effect of RNAi of selected target genes on both larval mortality and adult emergence of Cx. quinquefasciatus through two delivery methods: soaking and nanoparticles. Ten candidate genes were selected for RNAi based on their known lethal effect in other insects. Disruption of three genes, chitin synthase-1, inhibitor of apoptosis 1, and vacuolar adenosine triphosphatase, resulted in the highest mortality among the selected genes using the two treatment methods. Silencing the other seven genes resulted in a medium to low mortality in both assays. These three genes are also active against a wide range of insects and could be used for RNAi-based mosquito control in the future.
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Affiliation(s)
- Sayed M S Khalil
- Plant Protection Department, College of Food and Agricultural Sciences, King Saud University, Riyadh, Saudi Arabia
- Agricultural Genetic Engineering Research Institute, Agricultural Research Center, 9 Gamaa Street, Giza, Egypt
| | - Kashif Munawar
- Plant Protection Department, College of Food and Agricultural Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Azzam M Alahmed
- Plant Protection Department, College of Food and Agricultural Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Ahmed M A Mohammed
- Agricultural Genetic Engineering Research Institute, Agricultural Research Center, 9 Gamaa Street, Giza, Egypt
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Choudhury A, Verma S, Muthamilarasan M, Rajam MV. Identification of suitable reference genes for expression profiling studies using qRT-PCR in an important insect pest, Maruca vitrata. Mol Biol Rep 2021; 48:7477-7485. [PMID: 34637095 DOI: 10.1007/s11033-021-06766-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 09/15/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND Maruca vitrata is one of the potential insect pests that cause devastating losses to legume cultivation worldwide. Gene functional studies facilitate dissecting the molecular mechanisms underlying the infection process and enable devising appropriate molecular strategies to control this insect pest. Expression profiling using quantitative real-time PCR (qRT-PCR) provides insights into the functional characterization of target genes; however, ideal reference genes should be deployed in such studies to nullify the background variation and improve the accuracy of target gene expression. An ideal reference gene should have a stable expression across developmental stages, biological conditions, tissues, or experimental conditions. METHODS AND RESULTS Given this, the stability of eight candidate reference genes was evaluated in M. vitrata at different developmental stages, diets, and sexes by qRT-PCR method, and the data was analyzed using four independent algorithms, namely GeNorm, NormFinder, BestKeeper, and ΔCt, and one comprehensive algorithm, RefFinder. CONCLUSION The analysis showed that RP49 and RPL13 were the best suitable reference genes for studying target gene expression at different developmental stages. Further, the study identified RP49 and RPL24, and GAPDH and RPL24 as the ideal reference genes in M. vitrata fed with different diets and sexes, respectively. The reference genes reported in the present study will ensure the accuracy of target gene expression, and thus, will serve as an important resource for gene functional studies in M. vitrata.
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Affiliation(s)
- Aparajita Choudhury
- Department of Genetics, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
| | - Shubham Verma
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Telangana, 500046, India
| | - Mehanathan Muthamilarasan
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Telangana, 500046, India
| | - Manchikatla Venkat Rajam
- Department of Genetics, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India.
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Ahmad S, Jamil M, Fahim M, Zhang S, Ullah F, Lyu B, Luo Y. RNAi-Mediated Knockdown of Imaginal Disc Growth Factors (IDGFs) Genes Causes Developmental Malformation and Mortality in Melon Fly, Zeugodacus cucurbitae. Front Genet 2021; 12:691382. [PMID: 34290744 PMCID: PMC8287652 DOI: 10.3389/fgene.2021.691382] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 06/10/2021] [Indexed: 01/13/2023] Open
Abstract
This study reports the first successful use of oral feeding dsRNA technique for functional characterization of imaginal disc growth factors (IDGFs) genes (IDGF1, IDGF3_1, IDGF4_0, IDGF4_1, and IDGF6) in melon fly Zeugodacus cucurbitae. Phylogenetic and domain analysis indicates that these genes had high similarity with other Tephritidae fruit flies homolog and contain only one conserved domain among these five genes, which is glyco-18 domain (glyco-hydro-18 domain). Gene expression analysis at different developmental stages revealed that these genes were expressed at larval, pupal, and adult stages. To understand their role in different developmental stages, larvae were fed dsRNA-corresponding to each of the five IDGFs, in an artificial diet. RNAi-mediated knockdown of IDGF1 shows no phenotypic effects but caused mortality (10.4%), while IDGF4_0 caused malformed pharate at the adult stage where insects failed to shed their old cuticle and remained attached with their body, highest mortality (49.2%) was recorded compared to dsRNA-green fluorescent protein (GFP) or DEPC. Silencing of IDGF3_1 and IDGF4_1 cause lethal phenotype in larvae, (17.2%) and (40%) mortality was indexed in Z. cucurbitae. IDGF6 was mainly expressed in pupae and adult stages, and its silencing caused a malformation in adult wings. The developmental defects such as malformation in wings, larval–larval lethality, pupal–adult malformation, and small body size show that IDGFs are key developmental genes in the melon fly. Our results provide a baseline for the melon fly management and understanding of IDGFs specific functions in Z. cucurbitae.
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Affiliation(s)
- Shakil Ahmad
- School of Plant Protection, Hainan University, Haikou, China
| | - Momana Jamil
- School of Plant Protection, Hainan University, Haikou, China
| | - Muhammad Fahim
- Centre for Omic Sciences, Islamia College University, Peshawar, Pakistan
| | - Shujing Zhang
- School of Plant Protection, Hainan University, Haikou, China
| | - Farman Ullah
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, China
| | - Baoqian Lyu
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Integrated Pest Management on Tropical Crops, Ministry of Agriculture and Rural Affairs, Haikou, China
| | - Yanping Luo
- School of Plant Protection, Hainan University, Haikou, China
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Evaluating toxicity of Varroa mite (Varroa destructor)-active dsRNA to monarch butterfly (Danaus plexippus) larvae. PLoS One 2021; 16:e0251884. [PMID: 34077444 PMCID: PMC8171953 DOI: 10.1371/journal.pone.0251884] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 05/05/2021] [Indexed: 01/24/2023] Open
Abstract
Varroa mites (Varroa destructor) are parasitic mites that, combined with other factors, are contributing to high levels of honey bee (Apis mellifera) colony losses. A Varroa-active dsRNA was recently developed to control Varroa mites within honey bee brood cells. This dsRNA has 372 base pairs that are homologous to a sequence region within the Varroa mite calmodulin gene (cam). The Varroa-active dsRNA also shares a 21-base pair match with monarch butterfly (Danaus plexippus) calmodulin mRNA, raising the possibility of non-target effects if there is environmental exposure. We chronically exposed the entire monarch larval stage to common (Asclepias syriaca) and tropical (Asclepias curassavica) milkweed leaves treated with concentrations of Varroa-active dsRNA that are one- and ten-fold higher than those used to treat honey bee hives. This corresponded to concentrations of 0.025-0.041 and 0.211-0.282 mg/g leaf, respectively. Potassium arsenate and a previously designed monarch-active dsRNA with a 100% base pair match to the monarch v-ATPase A mRNA (leaf concentration was 0.020-0.034 mg/g) were used as positive controls. The Varroa mite and monarch-active dsRNA's did not cause significant differences in larval mortality, larval or pupal development, pupal weights, or adult eclosion rates when compared to negative controls. Irrespective of control or dsRNA treatment, larvae that consumed approximately 7500 to 10,500-mg milkweed leaf within 10 to 12 days had the highest pupal weights. The lack of mortality and sublethal effects following dietary exposure to dsRNA with 21-base pair and 100% base pair match to mRNAs that correspond to regulatory genes suggest monarch mRNA may be refractory to silencing by dsRNA or monarch dsRNase may degrade dsRNA to a concentration that is insufficient to silence mRNA signaling.
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Silver K, Cooper AM, Zhu KY. Strategies for enhancing the efficiency of RNA interference in insects. PEST MANAGEMENT SCIENCE 2021; 77:2645-2658. [PMID: 33440063 DOI: 10.1002/ps.6277] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 01/08/2021] [Accepted: 01/13/2021] [Indexed: 06/12/2023]
Abstract
Low RNA interference (RNAi) efficiency in many insect pests has significantly prevented its widespread application for insect pest management. This article provides a comprehensive review of recent research in developing various strategies for enhancing RNAi efficiency. Our review focuses on the strategies in target gene selection and double-stranded RNA (dsRNA) delivery technologies. For target gene selection, genome-wide or large-scale screening strategies have been used to identify most susceptible target genes for RNAi. Other strategies include the design of dsRNA constructs and manipulate the structure of dsRNA to maximize the RNA efficiency for a target gene. For dsRNA delivery strategies, much recent research has focused on the applications of complexed or encapsulated dsRNA using various reagents, polymers, or peptides to enhance dsRNA stability and cellular uptake. Other dsRNA delivery strategies include genetic engineering of microbes (e.g. fungi, bacteria, and viruses) and plants to produce insect-specific dsRNA. The ingestion of the dsRNA-producing organisms or tissues will have lethal or detrimental effects on the target insect pests. This article also identifies obstacles to further developing RNAi for insect pest management and suggests future avenues of research that will maximize the potential for using RNAi for insect pest management. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Kristopher Silver
- Department of Entomology, Kansas State University, Manhattan, KS, USA
| | | | - Kun Yan Zhu
- Department of Entomology, Kansas State University, Manhattan, KS, USA
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Akhtar ZR, Tariq K, Handler AM, Ali A, Ullah F, Ali F, Zang LS, Gulzar A, Ali S. Toxicological risk assessment of some commonly used insecticides on Cotesia flavipes, a larval parasitoid of the spotted stem borer Chilo partellus. ECOTOXICOLOGY (LONDON, ENGLAND) 2021; 30:448-458. [PMID: 33674904 DOI: 10.1007/s10646-021-02372-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/14/2021] [Indexed: 06/12/2023]
Abstract
Cotesia flavipes Cameron is an important larval parasitoid exploited for the control of the spotted stem borer, Chilo partellus (Swinhoe). Several studies have evaluated the toxic effects of insecticides on C. partellus, however, little is known about non-target effects of insecticides on this parasitoid, when used to control C. partellus. This laboratory study evaluated the lethal and sublethal effects of twelve insecticides on C. flavipes. Residual toxicity tests showed that organophosphates (chlorpyrifos, triazophos and profenofos) exhibited highest contact toxicity to C. flavipes adults with a LC50 range from 0.63 to 1.05 mg a.i/l, while neonicotinoids (nitenpyram, acetamiprid and imidacloprid) were less toxic to C. flavipes with a LC50 range from 1.27 to 139.48 mg a.i/l. Sugar-insecticide feeding bioassays showed that organophosphates, pyrethroids (cypermethrin, bifenthrin and lambda-cyhalothrin) and carbamates (thiodicarb, carbaryl and methomyl) were highly toxic to C. flavipes adults and caused 100% mortality at 48 h of exposure, while imidacloprid caused 66% mortality at 48 h of exposure. Risk quotient analysis showed that among all tested insecticides, imidacloprid and acetamiprid were less toxic to C. flavipes adults with a risk quotient value of 0.88 and 1.6, respectively. Furthermore, exposure of immature C. flavipes through their host bodies significantly decreased the parasitism rate at their F1 and F2 generations. Risk quotient analysis of insecticides indicated that imidacloprid and acetamiprid were the least toxic to C. flavipes. This study provides important information that will be used in incorporating the most suitable insecticides in integrated pest management programs with reduced negative impacts on non-target beneficial arthropods.
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Affiliation(s)
- Zunnu Raen Akhtar
- Department of Entomology, University of Agriculture Faisalabad, Faisalabad, Pakistan
| | - Kaleem Tariq
- Department of Entomology, Abdul Wali Khan University Mardan, Khyber Pakhtunkhwa, Pakistan.
- Entomology and Nematology Department, Steinmetz Hall, University of Florida, Gainesville, FL, 32611, USA.
- US Department of Agriculture, Agricultural Research Service, Center for Medical, Agricultural and Veterinary Entomology, Gainesville, FL, 32608, USA.
| | - Alfred M Handler
- US Department of Agriculture, Agricultural Research Service, Center for Medical, Agricultural and Veterinary Entomology, Gainesville, FL, 32608, USA
| | - Asad Ali
- Department of Entomology, Abdul Wali Khan University Mardan, Khyber Pakhtunkhwa, Pakistan
| | - Farman Ullah
- Department of Entomology, College of Plant Protection, China Agricultural University, 100193, Beijing, China
| | - Farman Ali
- Department of Entomology, Abdul Wali Khan University Mardan, Khyber Pakhtunkhwa, Pakistan
| | - Lian-Sheng Zang
- Key laboratory of green pesticides and agriculture bioengineering, Guizhou University, Guizhou, China
| | - Asim Gulzar
- Department of Entomology, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, Rawalpindi, Pakistan
| | - Sajjad Ali
- Department of Entomology, UCA & ES, The Islamia University of Bahawalpur, Bahawalpur, 63100, Pakistan
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Exogenous administration of dsRNA for the demonstration of RNAi in Maruca vitrata (lepidoptera: crambidae). 3 Biotech 2021; 11:197. [PMID: 33927988 DOI: 10.1007/s13205-021-02741-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 03/12/2021] [Indexed: 10/21/2022] Open
Abstract
The polyphagous spotted pod borer, Maruca vitrata is an important agricultural pest that causes extensive damage on various food crops. Though the pest is managed by synthetic chemicals, exploration of biotechnological approaches for its control is important. RNAi-based gene silencing is one such tool that has been extensively used for functional genomics and is highly variable in insects. In view of this, we have attempted to demonstrate RNAi in M. vitrata through exogenous double-stranded RNA (dsRNA) administration targeting seven genes associated with midgut, chemosensory, cell signalling and development. Two modes of exogenous dsRNA delivery by either haemolymph injection and/or ingestion into third and late third instar larval stages respectively exhibited efficient silencing of specific transcripts. Furthermore, dsRNA injection into the haemolymph showed significant reduction of target gene expression compared to negative controls establishing this mode of delivery to be more efficient. Interestingly, haemolymph injection required lesser dsRNA and led to higher reduction of transcript level vis-à-vis ingestion as demonstrated in dsRNA Serine Protease 33 (ds-SP33)-fed larvae. Over-expression of key RNAi component DICER and detection of siRNA authenticated the presence of RNAi in M. vitrata. Additionally, we have identified inhibitor molecules like morpholine, piperidine, carboxamide and piperidine-carboxamide through in silico analysis for blocking the function of SP33 to demonstrate the utility of functional genomics. Thus, the present study establishes the usefulness of injection and ingestion approaches for exogenous dsRNA delivery into M. vitrata larvae for effective RNAi. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s13205-021-02741-8.
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